diff --git a/plotting/matrix.R b/plotting/matrix.R
index 8479beb06ccc1af9273c86f6b09521a1f93ed25c..16750b96509ab76efcca743382ffdc29a0a5ff7c 100644
--- a/plotting/matrix.R
+++ b/plotting/matrix.R
@@ -288,12 +288,10 @@ matrix_panel = function (list_df2plot, df_meta, trend_period, mean_period, slice
                         df_data_code[df_data_code$Date >= Start_mean 
                                      & df_data_code$Date <= End_mean,]
                     
-                    # Min for the sub period
+                    # Min max for the sub period
                     Datemin = min(df_data_code_per$Date)
-                    
-                    # Max for the sub period
                     Datemax = max(df_data_code_per$Date)
-
+                    # Creates a period name
                     Periods = paste(Datemin, Datemax,
                                     sep=' / ')